Light guides are used in electronic devices to conduct light from one or more light sources to desired locations. As examples, there are known backlighted liquid crystal displays and illuminated keypads. Prior art solutions for uniformly illuminating a backlighted liquid crystal display are known for example from US 2005/0052732 A1; U.S. Pat. No. 6,592,233 B1; and US 2005/0213348 A1. Keypad illumination solutions are known for example from US 2005/0202787 A1; U.S. Pat. No. 6,550,927 B1; and U.S. Pat. No. 6,006,118 B1. A publication WO 03/047222 A1 discloses a combined solution for backlighting a display and illuminating a keypad with common components for generating and distributing light.
In some cases it is desirable to make the visual appearance of a user interface change depending on some affecting factor. For example, if the keys of a keypad have graphical markings on them to help the user visualize, which characters and/or functions are associated with each key, and such associations may vary depending on e.g. an operating mode of an electronic device that contains said keypad, it would increase the convenience of using the device if the correct key markings would appear in the correct orientation in each case.